The present disclosure relates to a solar powered intermittent operation based continuous absorption system to provide a refrigeration or cooling effect without the use of a solution pump. The air-conditioning and refrigeration sector consumes a lot of electrical energy produced, particular in hot climate regions. The coincidence of maximum cooling loads with the period of the highest solar irradiance makes solar energy a potential candidate for powering refrigeration and air conditioning systems and hence conserves a significant portion of electrical energy to be used in the production sector. In this regard, absorption air-conditioning and refrigeration systems (chillers) may have the potential to directly use solar energy.
Absorption chillers in the related art are basically classified into two main categories, intermittent operation systems and continuous operation systems. The basic difference between intermittent operation systems and continuous operation systems is their respective mode of operation. In intermittent operation systems, generation and absorption do not take place at the same time. Instead they intermittently follow each other within the operation of the system. In contrast, continuous operation systems have both generation and absorption take place at the same time in a continuous manner. Continuous absorption systems are comparatively much more developed than intermittent operation systems.
Another basic difference between these two systems is that continuous operation systems require a solution pump to pressurize the system, whereas intermittent operation systems uses isochoric process to pressurize the system. The reactive nature of ammonia solution requires that the solution pump in the continuous operation systems to be made of stainless steel. The stainless steel solution pump with high pressurization requirements makes the pump a very expensive component of continuous absorption systems. On the other hand, the intermittent operation systems do not require a solution pump since it uses an isochoric process for pressurization.
However, there are certain limitations of intermittent operation systems in the related art compared with the continuous operation systems in the related art. First, the intermittent absorption systems have low coefficient of performance compared with the continuous absorption systems. The low coefficient of performance is due to an inability of the intermittent operation systems to undergo a heat recovery process because the systems lack hot and cold solutions at the same time.
Second, the intermittent operation systems cannot produce refrigeration effect during the daytime when use of such systems is highly desired. This is due to the fact that refrigeration effect can only be produced during the absorption process, which takes place only at night time in the conventional intermittent operation systems. Third, the intermittent operation systems are set up such that they have a cycle time of approximately 24 hours which causes the systems' mass to increase considerably, for a specific cooling load requirement, thereby making the systems' mass much bulkier compared with continuous operation systems.
An object of the present disclosure is to provide an intermittent operation based continuous system that overcomes the above-mentioned problems and limitations of continuous operation systems and intermittent operation systems in the related art.